1. Field of the Invention
This invention relates to hydraulic coupling member. More particularly, it relates to undersea hydraulic couplings having pressure-energized metal seals.
2. Description of the Related Art
A wide variety of undersea hydraulic couplings are available. Some couplings employ metal seals. Examples of undersea hydraulic couplings having metal seals include: U.S. Pat. No. 4,694,859 for “Undersea hydraulic coupling and metal seal;” U.S. Pat. No. 4,817,668 for “Integral metal seal for hydraulic coupling;” U.S. Pat. No. 4,884,584 for “Internally preloaded metal-to-metal seal hydraulic connector;” U.S. Pat. No. 5,029,613 for “Hydraulic coupler with radial metal seal;” U.S. Pat. Nos. 5,099,882 and 5,203,374 for “Pressure balanced hydraulic coupling with metal seals;” U.S. Pat. No. 5,284,183 for “Hydraulic coupler with radial metal seal;” U.S. Pat. No. 5,339,861 for “Hydraulic coupling with hollow metal o-ring seal;” U.S. Pat. No. 5,355,909 for “Undersea hydraulic coupling with metal seals;” U.S. Pat. No. 5,979,499 for “Undersea hydraulic coupling with hollow metal seal;” U.S. Pat. No. 6,962,347 for “Metal backup seal for undersea hydraulic coupling;” and, U.S. Pat. No. 7,021,677 for “Seal retainer with metal seal members for undersea hydraulic coupling;” all to Robert E. Smith III and assigned to National Coupling Company of Stafford, Tex.
Other undersea hydraulic couplings employ only “soft seals”—i.e., non-metal seals that are typically formed of an elastomeric polymer (“elastomer”) or an engineering plastic capable of being machined such as polyetheretherketone (“PEEK”) or DELRIN® acetal resin.
U.S. Pat. No. 6,179,002 discloses an undersea hydraulic coupling having a radial pressure-energized seal with a dovetail interfit with the coupling body. The seal has a pair of flexible sealing surfaces for sealing with the male and female coupling members and a cavity therebetween that is exposed to fluid pressure in the coupling. The outer circumference of the seal has a dovetail interfit between inclined shoulders in the female member bore and on a seal retainer that holds the seal in the bore.
U.S. Pat. No. 6,575,430 discloses an undersea hydraulic coupling member having a ring-shaped seal with multiple scaling surfaces extending radially inwardly therefrom. The multiple sealing surfaces help guide the probe of the male coupling member into the female member without the risk of drag or galling of the receiving chamber. The seal has an interfit with reverse inclined shoulders in the female member to restrain the seal from moving radially inwardly due to vacuum or low pressure. Attention is invited in particular to the embodiments shown in FIGS. 8 and 9 of this patent.
U.S. Pat. No. 6,923,476 discloses a floating seal for an undersea hydraulic coupling member that is moveable radially to seal with the male coupling member even if there is some misalignment with the female coupling member. The floating seal is restricted from axial movement within the female coupling member receiving chamber. The floating seal may seal with the female coupling member.
U.S. Patent Application Publication No. US 2005/0029749 discloses an undersea hydraulic coupling member having a bore liner that protects the coupling members from galling during assembly or disassembly. The bore liner is removable from the bore of a female undersea hydraulic coupling member. The bore liner may be integral with a seal section that may seal with a male undersea hydraulic coupling member. The bore liner also may have an outer diameter configured to engage and interlock with the bore in which the bore liner is positioned. In certain embodiments, the bore liner is fabricated from PEEK.
U.S. Pat. No. 7,163,190 discloses an undersea hydraulic coupling member having a seal retainer with a first inner ring and a second outer ring. The first inner ring and second outer ring are concentric, at least part of the first inner ring inserted through the second outer ring. The second outer ring is threaded to the coupling member to provide sufficient torque to reduce or eliminate any gap between the seal retainer and the shoulder surface in the coupling member on which an elastomeric seal is positioned. Another elastomeric seal is held between the first inner ring and second outer ring of the seal retainer.
U.S. Pat. Nos. 6,983,940 and 7,201,381 to Halling are directed to a resilient, annular, metallic seal member having a generally J-shaped cross-section. The annular, metallic seal member includes a first end portion having a first distal end, a generally curled second end portion that extends to a second distal end, and a central body portion between and contiguous with the first and second end portions. The annular, metallic seal member has a first side and an opposite second side. The second end portion curls in a first direction in accordance with a predetermined radius such that the second distal end is located across from the first side of the annular, metallic seal member and the first and second distal ends do not face each other.